Expand and combine like terms. $(5+6b^3)^2=$
Explanation: We can expand this expression using the "perfect square" pattern (where $P$ and $Q$ can be any monomial): $(P+Q)^2=P^2+2PQ+Q^2$ $\begin{aligned} &\phantom{=}\left(5+6b^3\right)^2 \\\\ &=\left(5\right)^2+2\left(5\right)\left(6b^3\right)+\left(6b^3\right)^2 \\\\ &=25+60b^3+36b^6 \\\\ &=36b^6+60b^3+25 \end{aligned}$